Vacuum brake booster having a manual mode of operation and an electronic mode of operation is known in the prior art as evidenced by structure disclosed in U.S. Pat. Nos. 4,778,225; 5,096,267; 5,176,433 and 5,312,173 relating to the addition of traction control to a brake system and U.S. Pat. Nos. 5,226,173; 5,845,558; 5,772,290 and 6,065,388 relating to emergency braking features for a brake system. The structure in such brake systems functioned in an adequate manner for a purposed purpose at the time of such inventions however with the introduction of sway control features to a brake system such brake systems did not operate in a manner to provide for acceptable control of a brake system by an operator. For instance in some of the brake boosters having an emergency braking features, once an emergency brake application was initiated, the operator was prevented from intervening in the brake application unless the input force that initiated the emergency brake application was removed from a brake pedal. In U.S. Pat. Nos. 5,556,173 and 6,375,282 specific software and a switch are activated by a brake light switch to terminate an automatic braking.